(Perl) Verify HMAC XML Digital Signature

Demonstrates how to validate an XML digital signature signed with an HMAC key.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# The XML containing the Signature to be verified contains the following:

# <?xml version="1.0" encoding="UTF-8" standalone="no"?>
# <collection Id="root">
# 	<album>
# 		<title>Questions, unanswered</title>
# 		<artist>Steve and the flubberblubs</artist>
# 		<year>1989</year>
# 		<t:tracks xmlns:t="http://test.xades4j/tracks">
# 			<t:song length="4:05" tracknumber="1">
# 				<t:title>What do you know?</t:title>
# 				<t:artist>Steve and the flubberblubs</t:artist>
# 				<t:lastplayed>2006-10-17-08:31</t:lastplayed>
# 			</t:song>
# 			<t:song length="3:45" tracknumber="2">
# 				<t:title>Who do you know?</t:title>
# 				<t:artist>Steve and the flubberblubs</t:artist>
# 				<t:lastplayed>2006-10-17-08:35</t:lastplayed>
# 			</t:song>
# 			<t:song length="5:14" tracknumber="3">
# 				<t:title>When do you know?</t:title>
# 				<t:artist>Steve and the flubberblubs</t:artist>
# 				<t:lastplayed>2006-10-17-08:39</t:lastplayed>
# 			</t:song>
# 			<t:song length="4:19" tracknumber="4">
# 				<t:title>Do you know?</t:title>
# 				<t:artist>Steve and the flubberblubs</t:artist>
# 				<t:lastplayed>2006-10-17-08:44</t:lastplayed>
# 			</t:song>
# 		</t:tracks>
# 	</album>
# <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#"><ds:SignedInfo><ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/><ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#hmac-sha256"/><ds:Reference URI="#root"><ds:Transforms><ds:Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature"/></ds:Transforms><ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/><ds:DigestValue>rD/g8soqKz8EiPUBhEWfcQacS0ta4ULHX3dKMEH6ZoQ=</ds:DigestValue></ds:Reference></ds:SignedInfo><ds:SignatureValue>R8dXP95VRYJBfL6d0Peogybdk27+R+JIfX8jnVu0NOI=</ds:SignatureValue></ds:Signature></collection>

# The above XML is available at https://www.chilkatsoft.com/exampleData/hmacSigned.xml
# First fetch the XML..

$url = "https://www.chilkatsoft.com/exampleData/hmacSigned.xml";
$http = chilkat::CkHttp->new();
$sbXml = chilkat::CkStringBuilder->new();
$success = $http->QuickGetSb($url,$sbXml);
if ($success != 1) {
    print $http->lastErrorText() . "\r\n";
    exit;
}

$verifier = chilkat::CkXmlDSig->new();

# Load the XML containing the signature to be verified.
$success = $verifier->LoadSignatureSb($sbXml);
if ($success != 1) {
    print $verifier->lastErrorText() . "\r\n";
    exit;
}

# Provide the HMAC key
# The HMAC key for this signature is the us-ascii bytes of the string "secret",
# It can be set in any of the following ways (and also more ways not shown here..)
$verifier->SetHmacKey("secret","ascii");
# or
$verifier->SetHmacKey("c2VjcmV0","base64");
# or
$verifier->SetHmacKey("736563726574","hex");

# Verify the signature
$bVerified = $verifier->VerifySignature(1);
print "Signature verified = " . $bVerified . "\r\n";